Inverse association between prostatic polyunsaturated fatty acid and risk of locally advanced prostate carcinoma

BACKGROUND An effect of fatty acids has been implicated in men with advanced‐stage prostate carcinoma and in men who have died of the disease. To evaluate the influence of fatty acids in men with prostate carcinoma at earlier stages, the authors examined the relation between prostatic concentrations of fatty acids and locally advanced prostate carcinoma in men with clinically organ‐confined disease. METHODS Fatty acids were measured by capillary gas chromatography in fresh, nonmalignant prostate tissue specimens collected during surgery from 196 men undergoing radical prostatectomy for localized prostate carcinoma. Two‐sided, two‐sample Student t tests compared mean concentrations in men with extraprostatic disease (pT3–4N0–1M0) with control men with organ‐confined disease. Logistic regression accounted for clinical stage, prostate‐specific antigen level, Gleason sum, and other factors. RESULTS Percent total prostatic polyunsaturated fatty acid (PUFA) was found to be inversely associated with risk of locally advanced prostate carcinoma (n = 52) (odds ratio [OR] = 0.93, 95% confidence interval [95% CI], 0.87–0.99; P = 0.035). Risk of seminal vesicle involvement accounted for this association (OR = 0.86, 95% CI, 0.78–0.95; P = 0.003). Percent ω‐3 fatty acid (eicosapentanoic + docosahexanoic acids) and percent arachidonic acid also were found to be inversely related to the risk of seminal vesicle involvement (OR = 0.52, 95% CI, 0.30–0.90; P = 0.02; and OR = 0.84, 95% CI,; 0.75–0.95; P = 0.005, respectively). CONCLUSIONS Prostatic PUFA levels appear to influence the risk of locally advanced prostate carcinoma in men with clinically organ‐confined disease. This association may be mediated through the immune system. Cancer 2004. © 2004 American Cancer Society. Fatty acids influence the course of early‐stage prostate carcinoma. In the current study, the authors demonstrated that their effects are likely mediated through the immune system.